Issue #3392425 by quietone, smustgrave: Fix variable name spelling in non-tests, part1

core/lib/Drupal/Core/Datetime/DateHelper.php

core/lib/Drupal/Core/Datetime/TimeZoneFormHelper.php

core/lib/Drupal/Core/Extension/ExtensionDiscovery.php

core/lib/Drupal/Core/FileTransfer/FTPExtension.php

core/lib/Drupal/Core/StreamWrapper/LocalStream.php

core/misc/cspell/dictionary.txt

core/modules/filter/filter.module

core/modules/locale/locale.module

core/modules/locale/src/Form/TranslateEditForm.php

core/modules/media/src/Form/EditorMediaDialog.php

core/modules/mysql/src/Driver/Database/mysql/Schema.php

core/modules/node/src/Controller/NodeController.php

core/modules/node/src/NodeGrantDatabaseStorage.php

core/modules/pgsql/src/Driver/Database/pgsql/Schema.php

core/modules/search/src/SearchIndex.php

core/modules/search/src/SearchQuery.php

core/modules/taxonomy/src/Form/OverviewTerms.php

core/modules/text/text.module

core/modules/user/user.module

core/scripts/generate-d6-content.sh